1. Field of the Invention
The present invention relates generally to fluid powered guns and, more particularly, to a semi-automatic fluid powered gun in which a single charge of compressed fluid is used to blow back a slide assembly, fire a projectile, and recock the gun for subsequent firing.
2. Discussion of the Prior Art
Semi-automatic CO.sub.2 guns are known in the art for use in shooting pellets or other projectiles. An example of one such gun is shown in U.S. Pat. No. 2,817,328, issued to Gale on 24 Dec. 1957. The Gale patent illustrates the use of a gun in which pressurized CO.sub.2 is used to both fire the BB and cock the gun for a subsequent firing.
The gun disclosed in the Gale patent includes a frame presenting a main body, and an upper tubular part having a small-diameter forward region and a large-diameter rear bore. A barrel assembly is received in the upper tubular part, and includes a hollow barrel received in the forward region, and a piston and a rear extension received in the rear bore. A reciprocating hammer is supported within the body of the gun and is movable between forward and rear positions.
In the forward position, the hammer opens a valve, releasing CO.sub.2 into the upper tubular part forward of the piston so that the gas pressure forces the barrel assembly rearward. As this movement of the assembly occurs, the barrel is retracted, exposing a port through which pressurized gas enters the barrel and propels the BB from the gun. At the same time, the rearward piston movement causes the arm to retract the hammer, closing the valve. The hammer is retained in the cocked position by a latch that is released upon subsequent operation of a trigger of the gun.
The barrel of the gun illustrated in the Gale patent includes an opening forward of the port through which gas enters the barrel. This opening moves into alignment with a projectile storage clip in the forward position of the barrel assembly, and permits a single projectile to be loaded into the barrel. A small spring is positioned forward of the hole for preventing the projectile from falling out of the gun before it is fired, and a transverse pin extends through the barrel to prevent the projectile from rolling rearward into the bore of the upper tubular part of the frame.
Several shortcomings exist in conventional semi-automatic fluid powered guns which effect their efficiency and accuracy. For example, in guns of the type illustrated in the Gale patent, the entire barrel assembly reciprocates with each firing. Because of the weight of the assembly, more gas pressure is required to move the assembly than would be the case with a stationary barrel. Further, any holes, springs or other protuberances extending into the barrel create turbulence in the gas flow during firing, adversely effecting the accuracy of the gun. Such turbulence also reduces the power of the gun, thus discounting efficiency.
Another problem encountered in the use of conventional semi-automatic fluid powered guns resides in the concealment of the hammer within the frame such that it is difficult to verify the position of the hammer when cocked. It would be desirable to provide a gun that closely resembles an actual firearm, including a working slide and hammer that are positioned realistically.